Voice coil motors are broadly used in camera modules to drives focusing lenses and/or zoom lenses to move along an optical axis of the camera module. A voice coil motor includes a fixed part and a movable part being movable relative to the fixed part. A lens (for example focusing lens or zoom lens) is fixed on the movable part, when the voice coil motor is powered on, the movable part can drives the lenses along the optical axis of the camera module to a desired position, when the voice coil motor is powered off, the movable part can be driven to an original position by an elastic member of the voice coil motor.
During movement of the movable part to the original position, inertia of the movable part may prevent the movable part from stopping at the original position. Indeed, the inertia allows the movable part to continue in motion for a distance after the movable part reaches the original position. Therefore, the movable part and/or the lens may contact other part(s) of the camera module, such as a bracket and/or an IR glass of the camera module, and the parts of the camera module may be damaged by the movable part.